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1.
Brief Bioinform ; 24(2)2023 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-36702751

RESUMO

Recognizing binding sites of DNA-binding proteins is a key factor for elucidating transcriptional regulation in organisms. ChIP-exo enables researchers to delineate genome-wide binding landscapes of DNA-binding proteins with near single base-pair resolution. However, the peak calling step hinders ChIP-exo application since the published algorithms tend to generate false-positive and false-negative predictions. Here, we report the development of DEOCSU (DEep-learning Optimized ChIP-exo peak calling SUite), a novel machine learning-based ChIP-exo peak calling suite. DEOCSU entails the deep convolutional neural network model which was trained with curated ChIP-exo peak data to distinguish the visualized data of bona fide peaks from false ones. Performance validation of the trained deep-learning model indicated its high accuracy, high precision and high recall of over 95%. Applying the new suite to both in-house and publicly available ChIP-exo datasets obtained from bacteria, eukaryotes and archaea revealed an accurate prediction of peaks containing canonical motifs, highlighting the versatility and efficiency of DEOCSU. Furthermore, DEOCSU can be executed on a cloud computing platform or the local environment. With visualization software included in the suite, adjustable options such as the threshold of peak probability, and iterable updating of the pre-trained model, DEOCSU can be optimized for users' specific needs.


Assuntos
Sequenciamento de Cromatina por Imunoprecipitação , Aprendizado Profundo , Imunoprecipitação da Cromatina , Proteínas de Ligação a DNA/metabolismo , Software , Algoritmos , Sítios de Ligação , Análise de Sequência de DNA
2.
Am J Pathol ; 194(7): 1306-1316, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38588851

RESUMO

The role of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway in renal cell carcinoma (RCC) progression, metastasis, and resistance to therapies has not been investigated thoroughly. Transcription factor E3 (TFE3) expression is related to a poorer prognosis and tumor microenvironment in patients with RCC. This study aimed to determine the relationship between TFE3 and the PI3K/Akt pathway. TFE3 down-regulation was achieved by transient transfection of siRNA and shRNA in UOK146 cells. TFE3 overexpression was induced by transient transfection with pcDNA3.1 encoding the constitutively active form of TFE3. The cells were treated with mammalian target of rapamycin (mTOR) and PI3K inhibitors. Western blot was performed to detect TFE3, programmed death-ligand 1, phospho-Akt, and Akt. Phospho-Akt expression increased significantly upon TFE3 down-regulation, and decreased significantly upon up-regulation. When RCC cells were treated with a PI3K inhibitor (LY294002), TFE3 expression increased and phospho-Akt expression decreased. Data from this study indicate that TFE3 plays a role in the PI3K/Akt pathway in RCC. The results of this study suggest that PI3K/Akt inhibitors may aid in the treatment of patients with RCC by affecting the tumor microenvironment.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Carcinoma de Células Renais , Neoplasias Renais , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Serina-Treonina Quinases TOR , Microambiente Tumoral , Humanos , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/genética , Serina-Treonina Quinases TOR/metabolismo , Microambiente Tumoral/fisiologia , Neoplasias Renais/patologia , Neoplasias Renais/metabolismo , Neoplasias Renais/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/fisiologia , Linhagem Celular Tumoral , Fosfatidilinositol 3-Quinases/metabolismo , Regulação Neoplásica da Expressão Gênica
3.
Metab Eng ; 84: 13-22, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38796054

RESUMO

Acetate, a promising yet underutilized carbon source for biological production, was explored for the efficient production of homoserine and threonine in Escherichia coli W. A modular metabolic engineering approach revealed the crucial roles of both acetate assimilation pathways (AckA/Pta and Acs), optimized TCA cycle flux and glyoxylate shunt activity, and enhanced CoA availability, mediated by increased pantothenate kinase activity, for efficient homoserine production. The engineered strain W-H22/pM2/pR1P exhibited a high acetate assimilation rate (5.47 mmol/g cell/h) and produced 44.1 g/L homoserine in 52 h with a 53% theoretical yield (0.18 mol/mol) in fed-batch fermentation. Similarly, strain W-H31/pM2/pR1P achieved 45.8 g/L threonine in 52 h with a 65% yield (0.22 mol/mol). These results represent the highest reported levels of amino acid production using acetate, highlighting its potential as a valuable and sustainable feedstock for biomanufacturing.

4.
Ann Diagn Pathol ; 64: 152134, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37004359

RESUMO

Assigning a hepatocellular carcinoma (HCC) to an appropriate subtype is important because this guarantees the diagnosis and treatment and allows decisions regarding the prognosis of the patient. HCC subtyping is usually based on the World Health Organization (WHO) classification and the 2019 fifth edition is the latest version. However, the WHO classification system is still in evolution and has limited clinical relevance. We aimed to evaluate the clinical relevance of HCC subtyping and to reappraise some of the major subtypes of HCC. Our archived cases (n = 589) were reclassified according to the 2019 WHO system. The percentage of each subtype was mostly similar to that in the WHO classification. However, on the contrary to the 2019 WHO system, clear cell type HCC was associated with more frequent recurrence or metastasis. Meanwhile, macrotrabecular massive HCC was related to poor prognosis as demonstrated in the 2019 WHO system and should be described in the pathology report. For steatohepatitic HCC, there is a debate on whether it is a true subtype because the steatohepatitis morphology may or may not be present in the background liver. In our study, 44 % of steatohepatitic HCCs (n = 19/43) presented underlying steatohepatitis. Additionally, the background cirrhosis did not influence survival in the HCC patients, although the 2019 WHO system indicates the presence of cirrhosis as a poor prognostic factor. In conclusion, although it is not perfect yet, HCC subtyping based on the 2019 WHO system provides valuable information to manage patients with HCC.


Assuntos
Carcinoma Hepatocelular , Fígado Gorduroso , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Prognóstico , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/patologia , Fígado Gorduroso/patologia
5.
Am J Pathol ; 191(11): 1999-2008, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34358517

RESUMO

The efficacy of programmed death ligand (PD-L)-1/PD-1 checkpoint blockade in renal cell carcinoma (RCC) remains unknown. The effects of mTOR inhibitors are uncertain, and patients may develop resistance to them. The limited understanding of cancer cell-intrinsic mTOR-mediated pathways remains a challenge in developing effective treatments. Whether transcription factor (TF)-E3 regulates PD-L1 expression and the tumor microenvironment was investigated, and the effects of an mammalian target of rapamycin (mTOR) inhibitor on translocation RCC were explored. TFE3 was overexpressed in clear cell RCC cell lines, and PD-L1 expression was analyzed by Western blot analysis. PD-L1 activity in translocation RCC was analyzed in relation to TFE3 expression via TFE3 knockdown and treatment with an mTOR inhibitor. The results were correlated with the gene expression profile, evaluated using digital multiplex analysis. TFE3 and PD-L1 expression were positively correlated in RCC cells. TFE3 overexpression was associated with the expression of PD-L1 in RCC. Furthermore, mTOR inhibition was associated with enhanced PD-L1 expression via TFE3 activation in translocation RCC. These data support the feasibility of combination therapy based on mTOR inhibition and PD-L1 blockade as a novel strategy for the treatment of patients with translocation RCC.


Assuntos
Antígeno B7-H1/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Carcinoma de Células Renais/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Neoplasias Renais/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Linhagem Celular Tumoral , Humanos
6.
Exerc Sport Sci Rev ; 50(3): 145-155, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35152237

RESUMO

Recent studies have greatly advanced our understanding of the central role of mitochondria on endothelial function. Here, we propose a hypothesis that unidirectional laminar (pulsatile) flow and disturbed laminar (oscillatory) flow may differentially modulate mitochondrial phenotypes in the context of their bioenergetic, signaling, and biosynthetic functions, providing novel insights into subcellular mechanisms underlying how exercise benefits the improvement of vascular health.


Assuntos
Células Endoteliais , Endotélio Vascular , Células Cultivadas , Humanos , Mitocôndrias , Estresse Mecânico
7.
Sensors (Basel) ; 21(9)2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33926052

RESUMO

This study describes the development of a landslide monitoring system for the purpose of reducing damages caused by landslides in natural terrain. The system was developed to analyze the effects of landslide-inducing rainfall and the behavior of slopes through 12 monitoring stations that are distributed across eight national parks in Korea. Several sensors and a data acquisition equipment to monitor landslide were installed in each station. The composition of the system and its operating program were designed to efficiently manage the sizeable amounts of real-time monitoring data that are collected from the various stations. To test the potential of the developed system for reliable landslide hazard evaluations, data measured over a five-year period by the two monitoring stations in Jirisan National Park were analyzed. Subsequently, the suction stress of the soil over the monitoring period was calculated by applying laboratory test result of the geotechnical and unsaturated soil properties in the analysis domain area. The infinite slope stability analysis combined with an effective stress concept based on the suction stress was applied to calculate the factor of safety. This method also enabled the temporal and quantitative evaluation of slope stability in natural terrain. In addition, based on the monitoring and slope stability analysis results, an analysis for the spatial classification of landslide hazards was conducted. The analysis results quantitatively and statistically demonstrated that 98% of historical landslide initiation areas were classified as high hazard levels.

8.
Circulation ; 140(14): 1205-1216, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31769940

RESUMO

Mitochondria have emerged as a central factor in the pathogenesis and progression of heart failure, and other cardiovascular diseases, as well, but no therapies are available to treat mitochondrial dysfunction. The National Heart, Lung, and Blood Institute convened a group of leading experts in heart failure, cardiovascular diseases, and mitochondria research in August 2018. These experts reviewed the current state of science and identified key gaps and opportunities in basic, translational, and clinical research focusing on the potential of mitochondria-based therapeutic strategies in heart failure. The workshop provided short- and long-term recommendations for moving the field toward clinical strategies for the prevention and treatment of heart failure and cardiovascular diseases by using mitochondria-based approaches.


Assuntos
Sistema Cardiovascular , Educação/métodos , Insuficiência Cardíaca/terapia , Mitocôndrias/fisiologia , National Heart, Lung, and Blood Institute (U.S.) , Relatório de Pesquisa , Pesquisa Biomédica/métodos , Pesquisa Biomédica/tendências , Sistema Cardiovascular/patologia , Educação/tendências , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Humanos , National Heart, Lung, and Blood Institute (U.S.)/tendências , Relatório de Pesquisa/tendências , Pesquisa Translacional Biomédica/métodos , Pesquisa Translacional Biomédica/tendências , Estados Unidos/epidemiologia
9.
Am J Physiol Heart Circ Physiol ; 318(6): H1559-H1569, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32383993

RESUMO

Cerebrovascular dysfunction is a critical risk factor for the pathogenesis of Alzheimer's disease (AD). The purinergic P2Y2 receptor and endoplasmic reticulum (ER) stress are tightly associated with vascular dysfunction and the pathogenesis of AD. However, the protective effects of exercise training on P2Y2 receptor- and ER stress-associated cerebrovascular dysfunction in AD are mostly unknown. Control (C57BL/6, CON) and AD (APP/PS1dE9, AD) mice underwent treadmill exercise training (EX). 2-MeS-ATP-induced dose-dependent vasoreactivity was determined by using a pressurized posterior cerebral artery (PCA) from 10-12-mo-old mice. Human brain microvascular endothelial cells (HBMECs) were exposed to laminar shear stress (LSS) at 20 dyn/cm2 for 30 min, 2 h, and 24 h. The expression of P2Y2 receptors, endothelial nitric oxide synthase (eNOS), and ER stress signaling were quantified by Western blot analysis. Notably, exercise converted ATP-induced vasoconstriction in the PCA from AD mice to vasodilation in AD+EX mice to a degree commensurate to the vascular reactivity observed in CON mice. Exercise reduced the expression of amyloid peptide precursor (APP) and increased the P2Y2 receptor and Akt/eNOS expression in AD mice brain. Mechanistically, LSS increased the expression of both P2Y2 receptor and eNOS protein in HBMECs, but these increases were blunted by a P2Y2 receptor antagonist in HBMECs. Exercise also reduced the expression of aberrant ER stress markers p-IRE1, p/t-eIF2α, and CHOP, as well as Bax/Bcl-2, in AD mice brain. Collectively, our results demonstrate for the first time that exercise mitigates cerebrovascular dysfunction in AD through modulating P2Y2 receptor- and ER stress-dependent endothelial dysfunction.NEW & NOTEWORTHY A limited study has investigated whether exercise training can improve cerebrovascular function in Alzheimer's disease. The novel findings of the study are that exercise training improves cerebrovascular dysfunction through enhancing P2Y2 receptor-mediated eNOS signaling and reducing ER stress-associated pathways in AD. These data suggest that exercise training, which regulates P2Y2 receptor and ER stress in AD brain, is a potential therapeutic strategy for Alzheimer's disease.


Assuntos
Doença de Alzheimer/metabolismo , Circulação Cerebrovascular/fisiologia , Estresse do Retículo Endoplasmático/fisiologia , Condicionamento Físico Animal/fisiologia , Receptores Purinérgicos P2Y2/metabolismo , Doença de Alzheimer/fisiopatologia , Animais , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Camundongos , Óxido Nítrico Sintase Tipo III/metabolismo , Artéria Cerebral Posterior/metabolismo , Artéria Cerebral Posterior/fisiopatologia , Proteínas Proto-Oncogênicas c-akt/metabolismo
10.
Metab Eng ; 57: 1-12, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31626985

RESUMO

Methylotuvimicrobium alcaliphilum 20Z is a promising platform strain for bioconversion of one-carbon (C1) substrates into value-added products. To carry out robust metabolic engineering with methylotrophic bacteria and to implement C1 conversion machinery in non-native hosts, systems-level evaluation and understanding of central C1 metabolism in methanotrophs under various conditions is pivotal but yet elusive. In this study, a genome-scale integrated approach was used to provide in-depth knowledge on the metabolic pathways of M. alcaliphilum 20Z grown on methane and methanol. Systems assessment of core carbon metabolism indicated the methanol assimilation pathway is mostly coupled with the efficient Embden-Meyerhof-Parnas (EMP) pathway along with the serine cycle. In addition, an incomplete TCA cycle operated in M. alcaliphilum 20Z on methanol, which might only supply precursors for de novo synthesis but not reducing powers. Instead, it appears that the direct formaldehyde oxidation pathway supply energy for the whole metabolic system. Additionally, a comparative transcriptomic analysis in multiple gammaproteobacterial methanotrophs also revealed the transcriptional responses of central metabolism on carbon substrate change. These findings provided a systems-level understanding of carbon metabolism and new opportunities for strain design to produce relevant products from different C1-feedstocks.


Assuntos
Ciclo do Ácido Cítrico/fisiologia , Genoma Bacteriano , Glicólise/fisiologia , Metano/metabolismo , Metanol/metabolismo , Methylococcaceae , Carbono/metabolismo , Methylococcaceae/genética , Methylococcaceae/crescimento & desenvolvimento
11.
Ann Diagn Pathol ; 46: 151489, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32169826

RESUMO

According to the current 8th edition of the American Joint Committee of Cancer (AJCC), the T category of distal cholangiocarcinomas is classified based on the depth of invasion (DOI) (T1, < 5 mm; T2, between 5 and 12 mm; T3, > 12 mm). In consideration of the discrepancies between previous studies about the prognostic significance, we aimed to validate the current AJCC T staging system of distal cholangiocarcinomas. DOI was measured using three different methods: DOI1, DOI2, and DOI3. DOI1 was defined and stratified according to the AJCC 8th edition. DOI2 was measured as the distance from an imaginary curved line approximated along the distorted mucosal surface to the deepest invasive tumor cells. DOI3 was defined as the total tumor thickness. DOI2 and DOI3 were also divided into three categories using the same cut-off points as in the AJCC 8th edition. We compared these three DOI methods to the AJCC 7th edition as well. In contrast with the AJCC 7th edition, all three groups showed a correlation with patients' overall survival. Above all, the DOI2 group demonstrated the best significance in multivariate analysis. However, when the C indices were compared between these groups, differential significance proved to be negligible (DOI1 vs DOI2, p = 0.915; DOI2 vs DOI3, p = 0.057). Therefore, the measurement of DOI does not need to be rigorously and stringently performed. In conclusion, we showed that the current T classification system better correlates with the overall survival of patients with distal cholangiocarcinomas than the previous system.


Assuntos
Neoplasias dos Ductos Biliares/patologia , Colangiocarcinoma/patologia , Estadiamento de Neoplasias/métodos , Adulto , Idoso , Neoplasias dos Ductos Biliares/classificação , Neoplasias dos Ductos Biliares/mortalidade , Colangiocarcinoma/classificação , Colangiocarcinoma/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
12.
Anaerobe ; 64: 102236, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32623046

RESUMO

Clostridium perfringens is ubiquitous in the environment and the gastrointestinal tract of warm-blooded animals. While part of the gut microbiome, abnormal growth of C. perfringens causes histotoxic, neurologic, and enteric diseases in a variety of animal species, including humans, due to the production of toxins. There is extremely limited information on C. perfringens infection in non-human primates. Presently, 10 strains were successfully isolated from 126 monkeys and confirmed by molecular and biochemical analyses. All isolates were genotype A based on molecular analysis. Alpha toxin was identified in all isolates. Beta 2 toxin was detected in only three isolates. No other toxins, including enterotoxin, beta, iota, epsilon, and net B toxin, were identified in any isolate. All isolates were highly susceptible to ß-lactam antibiotics. Double hemolysis and lecithinase activity were commonly observed in all strains. Biofilm formation, which can increase antibiotic resistance, was identified in 90% of the isolates. The data are the first report the prevalence and characteristics of C. perfringens isolated from captive cynomolgus monkeys.


Assuntos
Toxinas Bacterianas/genética , Biofilmes/crescimento & desenvolvimento , Clostridium perfringens/efeitos dos fármacos , Clostridium perfringens/genética , Farmacorresistência Bacteriana Múltipla , Macaca fascicularis/microbiologia , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Infecções por Clostridium/microbiologia , Infecções por Clostridium/veterinária , Clostridium perfringens/isolamento & purificação , DNA Bacteriano/genética , Fezes/microbiologia , Feminino , Genótipo , Masculino , Filogenia , Prevalência , RNA Ribossômico 16S/genética , beta-Lactamas/farmacologia
13.
Int J Mol Sci ; 21(9)2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32384696

RESUMO

Alzheimer's disease is the most common neurodegenerative brain disease causing dementia. It is characterized by slow onset and gradual worsening of memory and other cognitive functions. Recently, parabiosis and infusion of plasma from young mice have been proposed to have positive effects in aging and Alzheimer's disease. Therefore, this study examined whether infusion of plasma from exercised mice improved cognitive functions related to the hippocampus in a 3xTg-Alzheimer's disease (AD) model. We collected plasma from young mice that had exercised for 3 months and injected 100 µL of plasma into the tail vein of 12-month-old 3xTg-AD mice 10 times at 3-day intervals. We then analyzed spatial learning and memory, long-term memory, hippocampal GSK3ß/tau proteins, synaptic proteins, mitochondrial function, apoptosis, and neurogenesis. In the hippocampus of 3xTg-AD mice, infusion of plasma from exercised mice improved neuroplasticity and mitochondrial function and suppressed apoptosis, ultimately improving cognitive function. However, there was no improvement in tau hyperphosphorylation. This study showed that plasma from exercised mice could have a protective effect on cognitive dysfunction and neural circuits associated with AD via a tau-independent mechanism involving elevated brain-derived neurotrophic factor due to exercise.


Assuntos
Disfunção Cognitiva/terapia , Hipocampo/metabolismo , Condicionamento Físico Animal/métodos , Troca Plasmática/métodos , Animais , Apoptose , Glicogênio Sintase Quinase 3 beta/metabolismo , Hipocampo/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Plasticidade Neuronal , Proteínas tau/metabolismo
14.
Int J Mol Sci ; 21(6)2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32188055

RESUMO

Plant growth-promoting rhizobacteria play vital roles not only in plant growth, but also in reducing biotic/abiotic stress. Sphingomonas panacis DCY99T is isolated from soil and root of Panax ginseng with rusty root disease, characterized by raised reddish-brown root and this is seriously affects ginseng cultivation. To investigate the relationship between 159 sequenced Sphingomonas strains, pan-genome analysis was carried out, which suggested genomic diversity of the Sphingomonas genus. Comparative analysis of S. panacis DCY99T with Sphingomonas sp. LK11 revealed plant growth-promoting potential of S. panacis DCY99T through indole acetic acid production, phosphate solubilizing, and antifungal abilities. Detailed genomic analysis has shown that S. panacis DCY99T contain various heavy metals resistance genes in its genome and the plasmid. Functional analysis with Sphingomonas paucimobilis EPA505 predicted that S. panacis DCY99T possess genes for degradation of polyaromatic hydrocarbon and phenolic compounds in rusty-ginseng root. Interestingly, when primed ginseng with S. panacis DCY99T during high concentration of iron exposure, iron stress of ginseng was suppressed. In order to detect S. panacis DCY99T in soil, biomarker was designed using spt gene. This study brings new insights into the role of S. panacis DCY99T as a microbial inoculant to protect ginseng plants against rusty root disease.


Assuntos
Tolerância a Medicamentos/genética , Genoma Bacteriano , Ferro/metabolismo , Panax/microbiologia , Sphingomonas/genética , Sphingomonas/fisiologia , DNA Bacteriano , Genes Bacterianos/genética , Tamanho do Genoma , Hidroxibenzoatos , Ferro/toxicidade , Metais Pesados , Desenvolvimento Vegetal , Raízes de Plantas/microbiologia , Microbiologia do Solo , Sphingomonas/efeitos dos fármacos , Sphingomonas/isolamento & purificação , Estresse Fisiológico
15.
J Mol Cell Cardiol ; 127: 232-245, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30611795

RESUMO

Sepsis is the overwhelming systemic immune response to infection, which can result in multiple organ dysfunction and septic shock. Myocardial dysfunction during sepsis is associated with advanced disease and significantly increased in-hospital mortality. Our group has shown that energetic failure and excess reactive oxygen species (ROS) generation constitute major components of myocardial dysfunction in sepsis. Because ROS production is central to cellular metabolic health, we tested if the synthetic anti-oxidant lignan secoisolariciresinol diglucoside (SDG; LGM2605) would alleviate septic cardiac dysfunction and investigated the underlying mechanism. Using the cecal ligation and puncture (CLP) mouse model of peritonitis-induced sepsis, we observed impairment of cardiac function beginning at 4 h post-CLP surgery. Treatment of mice with LGM2605 (100 mg/kg body weight, i.p.) 6 h post-CLP surgery reduced cardiac ROS accumulation and restored cardiac function. Assessment of mitochondrial respiration (Seahorse XF) in primary cardiomyocytes obtained from adult C57BL/6 mice that had undergone CLP and treatment with LGM2605 showed restored basal and maximal respiration, as well as preserved oxygen consumption rate (OCR) associated with spare capacity. Further analyses aiming to identify the cellular mechanisms that may account for improved cardiac function showed that LGM2605 restored mitochondria abundance, increased mitochondrial calcium uptake and preserved mitochondrial membrane potential. In addition to protecting against cardiac dysfunction, daily treatment with LGM2605 and antibiotic ertapenem (70 mg/kg) protected against CLP-associated mortality and reversed hypothermia when compared against mice receiving ertapenem and saline. Therefore, treatment of septic mice with LGM2605 emerges as a novel pharmacological approach that reduces cardiac ROS accumulation, protects cardiac mitochondrial function, alleviates cardiac dysfunction, and improves survival.


Assuntos
Butileno Glicóis/síntese química , Butileno Glicóis/uso terapêutico , Cardiomiopatias/complicações , Cardiomiopatias/tratamento farmacológico , Glucosídeos/síntese química , Glucosídeos/uso terapêutico , Mitocôndrias Cardíacas/metabolismo , Miócitos Cardíacos/metabolismo , Sepse/complicações , Sepse/tratamento farmacológico , Animais , Antioxidantes/metabolismo , Autofagia/efeitos dos fármacos , Biomarcadores/metabolismo , Butileno Glicóis/química , Butileno Glicóis/farmacologia , Cálcio/metabolismo , Cardiomiopatias/genética , Cardiomiopatias/fisiopatologia , Ceco/patologia , Linhagem Celular , Citocinas/sangue , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Glucosídeos/química , Glucosídeos/farmacologia , Humanos , Mediadores da Inflamação/metabolismo , Ligadura , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Mitocôndrias Cardíacas/efeitos dos fármacos , Miocárdio/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , NF-kappa B/metabolismo , Biogênese de Organelas , Estresse Oxidativo/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Punções , Sepse/genética , Sepse/fisiopatologia
16.
J Physiol ; 596(18): 4413-4426, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30099751

RESUMO

KEY POINTS: Referring to the muscle memory theory, previously trained muscles acquire strength and volume much faster than naive muscles. Using extreme experimental models such as synergist ablation or steroid administration, previous studies have demonstrated that the number of nuclei increases when a muscle becomes enlarged, which serves as a cellular muscle memory mechanism for the muscle. In the present study, we found that, when rats were subjected to physiologically relevant resistance training, the number of myonuclei increased and was retained during a long-term detraining period. The acquired myonuclei were related to a greater degree of muscle hypertrophic and mitochondrial biogenesis processes following subsequent hypertrophic conditions. Our data suggest a cellular mechanism supporting the notion that exposing young muscles to resistance training would help to restore age-related muscle loss coupled with mitochondrial dysfunction in later life. ABSTRACT: Muscle hypertrophy induced by resistance training is accompanied by an increase in the number of myonuclei. The acquired myonuclei are viewed as a cellular component of muscle memory by which muscle enlargement is promoted during a re-training period. In the present study, we investigated the effect of exercise preconditioning on mitochondrial remodelling induced by resistance training. Sprague-Dawley rats were divided into four groups: untrained control, training, pre-training or re-training. The training groups were subjected to weight loaded-ladder climbing exercise training. Myonuclear numbers were significantly greater (up to 20%) in all trained muscles compared to untrained controls. Muscle mass was significantly higher in the re-training group compared to the training group (∼2-fold increase). Mitochondrial content, mitochondrial biogenesis gene expression levels and mitochondrial DNA copy numbers were significantly higher in re-trained muscles compared to the others. Oxidative myofibres (type I) were significantly increased only in the re-trained muscles. Furthermore, in vitro studies using insulin-like growth factor-1-treated L6 rat myotubes demonstrated that myotubes with a higher myonuclear number confer greater expression levels of both mitochondrial and nuclear genes encoding for constitutive and regulatory mitochondrial proteins, which also showed a greater mitochondrial respiratory function. These data suggest that myonuclei acquired from previous training facilitate mitochondrial biogenesis in response to subsequent retraining by (at least in part) enhancing cross-talk between mitochondria and myonuclei in the pre-conditioned myofibres.


Assuntos
Mitocôndrias Musculares/metabolismo , Fibras Musculares Esqueléticas/fisiologia , Biogênese de Organelas , Condicionamento Físico Animal , Animais , Núcleo Celular/metabolismo , DNA Mitocondrial/genética , Feminino , Fibras Musculares Esqueléticas/metabolismo , Força Muscular , Ratos , Ratos Sprague-Dawley
17.
N Engl J Med ; 368(11): 1027-32, 2013 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-23484829

RESUMO

There is growing evidence that alterations in metabolism may contribute to tumorigenesis. Here, we report on members of families with the Li-Fraumeni syndrome who carry germline mutations in TP53, the gene encoding the tumor-suppressor protein p53. As compared with family members who are not carriers and with healthy volunteers, family members with these mutations have increased oxidative phosphorylation of skeletal muscle. Basic experimental studies of tissue samples from patients with the Li-Fraumeni syndrome and a mouse model of the syndrome support this in vivo finding of increased mitochondrial function. These results suggest that p53 regulates bioenergetic homeostasis in humans. (Funded by the National Heart, Lung, and Blood Institute and the National Institutes of Health; ClinicalTrials.gov number, NCT00406445.).


Assuntos
Metabolismo Energético/genética , Exercício Físico/fisiologia , Genes p53 , Síndrome de Li-Fraumeni/metabolismo , Mitocôndrias Musculares/metabolismo , Fosfocreatina/metabolismo , Animais , Estudos de Casos e Controles , Modelos Animais de Doenças , Feminino , Mutação em Linhagem Germinativa , Heterozigoto , Humanos , Síndrome de Li-Fraumeni/genética , Masculino , Camundongos , Músculo Esquelético/metabolismo , Consumo de Oxigênio/genética , Consumo de Oxigênio/fisiologia , Projetos Piloto , Levantamento de Peso/fisiologia
18.
Am J Physiol Heart Circ Physiol ; 309(3): H425-33, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26024684

RESUMO

The concept of enhancing structural integrity of mitochondria has emerged as a novel therapeutic option for cardiovascular disease. Flow-induced increase in laminar shear stress is a potent physiological stimulant associated with exercise, which exerts atheroprotective effects in the vasculature. However, the effect of laminar shear stress on mitochondrial remodeling within the vascular endothelium and its related functional consequences remain largely unknown. Using in vitro and in vivo complementary studies, here, we report that aerobic exercise alleviates the release of endothelial microparticles in prehypertensive individuals and that these salutary effects are, in part, mediated by shear stress-induced mitochondrial biogenesis. Circulating levels of total (CD31(+)/CD42a(-)) and activated (CD62E(+)) microparticles released by endothelial cells were significantly decreased (∼40% for both) after a 6-mo supervised aerobic exercise training program in individuals with prehypertension. In cultured human endothelial cells, laminar shear stress reduced the release of endothelial microparticles, which was accompanied by an increase in mitochondrial biogenesis through a sirtuin 1 (SIRT1)-dependent mechanism. Resveratrol, a SIRT1 activator, treatment showed similar effects. SIRT1 knockdown using small-interfering RNA completely abolished the protective effect of shear stress. Disruption of mitochondrial integrity by either antimycin A or peroxisome proliferator-activated receptor-γ coactivator-1α small-interfering RNA significantly increased the number of total, and activated, released endothelial microparticles, and shear stress restored these back to basal levels. Collectively, these data demonstrate a critical role of endothelial mitochondrial integrity in preserving endothelial homeostasis. Moreover, prolonged laminar shear stress, which is systemically elevated during aerobic exercise in the vessel wall, mitigates endothelial dysfunction by promoting mitochondrial biogenesis.


Assuntos
Micropartículas Derivadas de Células/metabolismo , Exercício Físico , Células Endoteliais da Veia Umbilical Humana/metabolismo , Renovação Mitocondrial , Pré-Hipertensão/metabolismo , Selectina E/genética , Selectina E/metabolismo , Feminino , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Mitocôndrias/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Complexo Glicoproteico GPIb-IX de Plaquetas/genética , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Pré-Hipertensão/sangue , Fluxo Sanguíneo Regional , Resveratrol , Sirtuína 1/genética , Sirtuína 1/metabolismo , Estilbenos/farmacologia , Estresse Mecânico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
19.
Ethn Dis ; 25(4): 413-8, 2015 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-26674844

RESUMO

BACKGROUND: African Americans have a predisposition to heightened systemic inflammation and a high prevalence of hypertension. OBJECTIVE: The purpose of this study was to evaluate the influence of interleukin-10 (IL-10) and laminar shear stress (LSS) on African American endothelial cells by measuring total endothelial nitric oxide synthase (eNOS) protein expression and its phosphorylated form (p-eNOS) at Serine 1177, and nitric oxide (NO) levels, in response to IL-10 incubation and high physiological levels of LSS, used as an in vitro mimetic for aerobic exercise training (AEXT). DESIGN: Human umbilical vein endothelial cells (HUVEC) from an African American donor were cultured. The experimental conditions included Static, Static with IL-10 Incubation, LSS at 20 dynes/cm², and LSS at 20 dynes/cm² with IL-10 Incubation. Western blotting was used to measure eNOS and p-eNOS protein expression in the cells. A modified Griess assay was used to measure NO metabolites in the cell culture media. RESULTS: There were significant increases in p-eNOS, eNOS, and NO in the LSS at 20 dynes/cm² and LSS at 20 dynes/cm² with IL-10 Incubation experimental conditions when compared to the Static experimental condition. There were no other statistically significant differences demonstrating that IL-10 did not have an additive effect on eNOS activity in our study. CONCLUSION: The significant increases in p-eNOS, eNOS, and NO as a result of LSS in African American HUVECs suggest that AEXT may be a viable, nonpharmacologic method to improve vascular inflammation status and vasodilation, and thereby contribute to hypertension reduction in the African American population.


Assuntos
Negro ou Afro-Americano , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Interleucina-10/farmacologia , Óxido Nítrico Sintase Tipo III/metabolismo , Óxido Nítrico/metabolismo , Estresse Mecânico , Técnicas de Cultura de Células , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Resistência ao Cisalhamento
20.
mSystems ; 9(1): e0094323, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38085058

RESUMO

Antimicrobial resistance (AMR) in pathogenic bacteria poses a significant threat to public health, yet there is still a need for development in the tools to deeply understand AMR genes based on genetic or structural information. In this study, we present an interactive web database named Blanket Overarching Antimicrobial-Resistance gene Database with Structural information (BOARDS, sbml.unist.ac.kr), a database that comprehensively includes 3,943 reported AMR gene information for 1,997 extended spectrum beta-lactamase (ESBL) and 1,946 other genes as well as a total of 27,395 predicted protein structures. These structures, which include both wild-type AMR genes and their mutants, were derived from 80,094 publicly available whole-genome sequences. In addition, we developed the rapid analysis and detection tool of antimicrobial-resistance (RADAR), a one-stop analysis pipeline to detect AMR genes across whole-genome sequencing (WGSs). By integrating BOARDS and RADAR, the AMR prevalence landscape for eight multi-drug resistant pathogens was reconstructed, leading to unexpected findings such as the pre-existence of the MCR genes before their official reports. Enzymatic structure prediction-based analysis revealed that the occurrence of mutations found in some ESBL genes was found to be closely related to the binding affinities with their antibiotic substrates. Overall, BOARDS can play a significant role in performing in-depth analysis on AMR.IMPORTANCEWhile the increasing antibiotic resistance (AMR) in pathogen has been a burden on public health, effective tools for deep understanding of AMR based on genetic or structural information remain limited. In this study, a blanket overarching antimicrobial-resistance gene database with structure information (BOARDS)-a web-based database that comprehensively collected AMR gene data with predictive protein structural information was constructed. Additionally, we report the development of a RADAR pipeline that can analyze whole-genome sequences as well. BOARDS, which includes sequence and structural information, has shown the historical landscape and prevalence of the AMR genes and can provide insight into single-nucleotide polymorphism effects on antibiotic degrading enzymes within protein structures.


Assuntos
Antibacterianos , Farmacorresistência Bacteriana , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Prevalência , Mutação , Bactérias/genética
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